People living in northern areas often encounter frozen locks. Motor vehicle locks are especially susceptible to this problem.
The prior art teaches electic resistance heating devices which thaw the lock such as in U.S. Pat. Nos. 2,530,513; 3,192,359; 3,662,149; 2,538,872 and 2,774,855. Other devices heat the key which in turn thaws the lock. Key heaters of the electric as in U.S. Pat. No. 3,450,859 and fossil fuel as in U.S. Pat. No. 3,023,749 varieties have been developed. A protable chemical stream generator in U.S. Pat. No. 2,621,648 thaws the lock with a jet of steam.
All of the devices in the prior art require power of some sort, such as electrical or chemical, for their operation.